Yeah, I have, did a 9-monther through them that ended just short of a year ago. They changed companies halfway through my contract, I have a previous post here asking about that. In practice, nothing changed for me, and their main trading vehicle is TVWW.
Their agents are a little young and wet-behind-the-ears imo (or maybe I'm just getting old!) but they got the job done okay. Contract went through easily. In fact, they upped the agreed rate by a fiver a day once the final purchase order came through from the client.
For payments, I had one month where payment wasn't received on time. Chased with the agent and there was a week or so of faffing about but it all got cleared up in the end. Final invoice was paid without issues, and expenses invoices went through okay (for clarity, these were for non-standard off-site travel to the EU, not the normal Monday-to-Friday travel). Payment terms were not the best (monthly, with payment being the month after invoice is received, so payment for January would be received in the first week of March) but you could probably negotiate better.
For agent contact they were quite good. Rang me every two months or so to check how things were (often enough to keep in touch, distant enough to let me get on with the job). I actually walked away from this contract after the 9 months (handed in the correct amount of notice, etc) and they were decent about it. They still call me every now and then to see what I'm up to, and whether I can place any of their contractors
